1. Field of the Invention
The present invention relates to helical coil vending machines which are also known as spiral venders. More particularly, the present invention relates to the elongated helical dispensing coils customarily used in this type of vending machine.
2. Description of the Prior Art
Automated vending machines which dispense a selected food product upon insertion by a purchaser of a required amount of money are well known. Such vending machines have various kinds of dispensing mechanisms depending upon the particular type of food product which is being vended. One well known class of such vending machines are those known in the trade as helical coil vending machines or, alternatively, as spiral venders. These machines are widely used for dispensing pre-packaged food products of the type containing pastries, potato chips, candy bars and the like.
Helical coil dispensing machines customarily include a housing which supports a plurality of vertically spaced shelves. Each of the shelves usually includes a plurality of elongated dispensing coils which run from front to back on the shelf. The rear end of each dispensing coil is operatively connected to an electric motor for selectively rotating the coil. In addition, each of the coils contains a plurality of food products which are received between the convolutions of the coil. These food products will ride along the surface of the shelf as they are moved forward in a step-by-step manner by consecutive rotations of the coil. Finally, the products are dispensed over the forward edge of the shelf where they fall down through a discharge space into a discharge bin for manual removal by the purchaser.
In the usual situation where the food products contact or slide along the shelf surface as they are received between the convolutions of the coils, certain food products are sometimes difficult to vend properly. For example, some food products, usually relatively heavy pastry products such as donuts and the like, are often wrapped in a saran wrap type of wrapping. As is commonly known, this type of wrapping tends to cling or stick to various things in part because of its composition. Thus, when food products wrapped in such a material are contained between the convolutions of the coil, they are likely to cling or stick to various portions of the shelf surface. Sometimes, such products cling to the shelf with such force that the dispensing coil becomes jammed rendering it inoperative. This requires that a serviceman clear the jammed coil before the products contained therein can be further vended. The need for such servicing, which may be quite frequent in this situation, is generally disadvantageous and costly.
Certain vending machines are known which utilize an insert member that longitudinally runs through the interior of the convolutions of the coil. These insert members define support surfaces which at least partially support the food products contained in the coil. Typical examples of such support surfaces are shown in U.S. Pat. No. 3,335,907 to Holstein et al and U.S. Pat. No. 3,344,953 to Krakauer et al. While such support surfaces are sometimes configured to support the food products above the shelf of the machine which inherently limits contact of the products with the shelf, the food products themselves will often tend to cling to various portions of the support surfaces. This is due at least partially to the fact that such support surfaces are fixedly mounted relative to the coil. In addition, the support surfaces also extend through the discharge end of the coil to terminate in front of the coil. Thus, as the food products are being vended from the last convolution at the discharge end of the coil, the vended products sometimes have a tendency to cling to or rest on the support surface even after being vended. In addition, such support surfaces sometimes only serve as a continuation of the horizontal shelf in the vending machine. In this case, they do not even partially alleviate the problem of the food products having a tendency to stick to the shelf surface.